Bologna, August 18, 2026 – A new disturbance is arriving in central northern Italy with a drop in temperatures. The territory is balanced between heat and downpours. And after the bad weather wave that hit Emilia Romagna in recent hours, the region will have to deal again with weather characterized by instability. Despite the drop in temperatures recorded after Ferragosto, the heat alert rises again, according to the latest bulletin issued by the Ministry of Health: orange alert Thursday 20 in Bologna. The city of the Two Towers will be one of the five where the heat alert rises. Friday, August 21, the new disturbance arrives. According to Arpae forecasts, “the presence of a depression wave will determine very cloudy sky conditions throughout the period with possible showers also of a thunderstorm nature, especially in the first part of the trend. Temperatures will therefore undergo a slight decrease, settling around maximum values of 27/30 degrees.” The bad weather with possible thunderstorms should also extend to Saturday 22. Instability is expected until Monday, August 24.
Waterspouts sighted between Riccione and Cattolica
Meanwhile this morning, waterspouts off the Rimini coast and between Riccione and Cattolica. “Not an unusual event – explains Roberto Nanni, Ampro weather technician –, but it is the residual instability confined to a thundercloud that around 8 left the Romagna borders heading towards the central-southern regions.”
“The waterspout, or waterspout – explains the expert –, is an atmospheric vortex that develops above the sea surface and which, in our areas, can also form in the presence of thunderclouds that are not particularly imposing. In many cases, a congested cumulus with intense upward currents is sufficient, without necessarily having a mature thunderstorm. An important role is played by the warm sea, which provides heat and humidity to the lower layers of the atmosphere, favoring convection. The presence of convergence and vorticity near the surface can therefore be amplified by the upward currents, giving rise to the characteristic vortex. The reduced friction of the sea surface, much lower than that exerted by the land, also contributes to its development. The result is often a narrow, elongated, and sinuous structure, apparently fragile but still capable of producing very strong gusts and even significant damage, especially if it reaches the coast.”
The most common waterspouts
“However, an important distinction must be made – emphasizes Nanni -: not all waterspouts are the same. The most common in the Mediterranean are generally misocyclonic phenomena (like those that appeared this morning), while more rarely a waterspout can develop inside a supercell: in this case, it is called a tornadic waterspout and the intensity can be decidedly greater. It is precisely this variety of mechanisms that makes waterspouts a particularly interesting phenomenon and, sometimes, difficult to predict in detail.”
“Temperature drop in the north”
From Friday a new thermal drop is expected. “The bad weather phase – explained 3bmeteo meteorologist, Manuel Mazzoleni – will be associated with a new drop in temperatures in the North and part of the Center, with maximums that at times will also fall below 30°C. From Friday in many cities in the Northwest, maximums will struggle to reach 26/27°C, as well as in part of Triveneto, while between Emilia-Romagna and the central regions they will oscillate between about 28 and 32°C. A drop is also expected in minimums with values even below 20°C in the North. The trend finally sees bad weather again at the beginning of next week in the North (to be confirmed) and local instability in the Center with temperatures still in line with the period averages or locally even below.”
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Forecast for Wednesday, August 19
Wednesday the sky will be clear or slightly cloudy due to the passage of high clouds, with greater cloudiness on the plains in the afternoon; wide clearings expected in the evening. Temperatures minimum stationary around 21/22 degrees, maximum slightly increasing with values around 32/33 degrees on the coast and 35 with peaks of 36 degrees in the more inland plains. Winds mainly from the southwest with local reinforcements or gusts up to the plains towards evening. Sea slightly rough, with wave motion intensifying to rough from late afternoon.
What will the weather be like on August 20?
In the morning the sky will be almost clear or slightly cloudy, with a gradual increase in cloudiness from the afternoon and from the evening a flow from the southwest will determine thunderstorm showers that from the westernmost sectors will gradually extend over the entire territory. Temperatures rising, with minimums around 23/24 degrees and maximums around 33/34 degrees on the coast and around 36 degrees in the plains. Winds mainly from the southwest with reinforcements and gusts from the early hours of the day, from late afternoon/evening linked to the passage of thunderstorms. Rough sea, with wave motion intensifying to rough from the afternoon.
Trend from August 24 to 30
According to Arpae “the pressure field dip, more pronounced over Western Europe, should still affect our region at times with increased instability. Therefore, episodes of precipitation with quantities slightly above the period norm appear probable, somewhat more pronounced on the hills and western plains. Temperatures will return to values within the climatological average or even slightly lower.”
